In June 2026, we announced that enrollment in BHV7000-303 was complete. Dosing continues and topline data readout remains on timeline for the second half of 2026. As part of the nonclinical characterization of certain metabolites of BHV-7000 observed in rodent testing, an update was provided to global regulatory authorities regarding these ongoing nonclinical studies. It was determined that there was insufficient information related to a specific metabolite to assess risks of that metabolite to human subjects at this time. Thus, FDA instructed the Company to pause new enrollment until additional clarifying nonclinical studies are completed, and issued a partial clinical hold letter on September 4, 2026 that pauses new patient enrollment pending the results of additional nonclinical data regarding the metabolite. The partial clinical hold applies to new patient enrollment only. Dosing continues for all patients already randomized across the BHV-7000 program, more than 600 patients. BHV7000-303, one of two pivotal studies in refractory focal epilepsy, is fully enrolled and randomized. Dosing continues in BHV7000-303 and topline data remain on track for the second half of 2026.

Until the additional nonclinical data are available in the coming weeks, specific near-term implications regarding the development program are as follows:

•Dosing of already randomized patients is allowed to continue across the BHV-7000 program while waiting for the additional nonclinical data to further characterize this metabolite.

•There is no impact to the BHV7000-303 timelines as study enrollment and randomization was previously completed. Dosing remains ongoing in BHV7000-303 and topline data continues to be on timelines for the second half of 2026.

•BHV7000-302 will also continue dosing but new enrollment is paused pending nonclinical data that is expected in the coming weeks to further elucidate findings related to this metabolite that have uncertain significance in humans. Additionally, the OLE study continues dosing.

•Biohaven voluntarily instituted this plan to its global sites outside of the U.S.

The significance of the nonclinical metabolite findings to humans is uncertain. The findings may be specific to rodents and not relevant to human safety, and the additional nonclinical studies underway are intended to address that question. BHV-7000 has generally been safe and well-tolerated in clinical studies with over 1,200 participants dosed to date.

On August 26, 2026, Biohaven Bioscience Ireland Limited ("BBIL"), a wholly owned subsidiary of the Company, entered into a License Agreement (the "License Agreement") with SK Biopharmaceuticals Co., Ltd. ("SKBP"). Pursuant to the License Agreement, effective upon the closing of the transactions contemplated thereby, SKBP will have an exclusive, royalty-bearing, worldwide license, with the right to grant sublicenses subject to the terms of the License Agreement, to Biohaven’s Kv7 ion channel platform, including BHV-7000 as well as other Kv7 compounds and products covered by the License Agreement. All clinical and nonclinical data, including those related to the metabolite characterization submitted to global regulatory authorities, was fully disclosed to SKBP prior to the signing of the License Agreement. Biohaven and SKBP continue to work on the completion of the required Hart-Scott-Rodino ("HSR") submission required for closing.

In January 2024, we completed our End-of-Phase 2 meeting with the U.S. Food and Drug Administration ("FDA") to advance to Phase 3 trials and announced that more than 110 global clinical sites have been selected in the first of two focal epilepsy trials (BHV7000-302 and BHV7000-303). Enrollment in our Phase 2/3 program commenced in the first quarter of 2024. The two pivotal studies evaluating the efficacy of BHV-7000 in refractory focal epilepsy are randomized, double-blind, placebo-controlled, 8- and 12-week trials with a primary endpoint of change from baseline in 28-day average seizure frequency in adults with focal epilepsy. BHV7000-303 is evaluating 50 mg and 75 mg doses of BHV-7000. BHV7000-201 is the associated open-label extension ("OLE") study. The clinical safety profile of BHV-7000 has generally been safe and well-tolerated to date with over 1,200 participants dosed with BHV-7000 across the development program.